Effect of Pre-cooking Time on the Quality of Noodles during Frozen Storage

In this study, the changes of cooking quality, texture property, moisture content, state of moisture, sensory property, thermal stability and microstructure of noodles pre-cooking for 0, 1, 3, 5 minutes during frozen storage (1, 30, 60, 90, 120 days) were investigated. The effects of different pre-cooking time on the frozen storage quality characteristics of noodles were discussed. The results showed that when the precooking time increased from 0 min to 5 min at 1 day of freezing, the hardness and viscosity of noodles decreased, the cooking loss rate and water absorption of precooking process increased significantly (P<0.05), and the sensory score decreased from 88.40 to 81.40. After frozen storage for 120 days, the water absorption of raw noodles and pre-cooking noodles with 1, 3 and 5 minutes decreased by 12.82%, 17.04%, 15.61% and 11.33%, and the viscosity increased by 83.58%, 40.69%, 27.63% and 19.50%, and the sensory score decreased by 21.50, 18.36, 10.96 and 0.51. Pre-cooking treatment could delay the quality deterioration in the process of freezing storage, improve the surface stickiness of noodles and the sensory quality of noodles after frozen storage. Pre-cooking for 5 minutes could achieve the optimum effect. After pre-cooking, the water content of noodles increased, the proportion of free water increased, and the deeply bound water and weakly bound water decreased. At the same time, the continuity of gluten network structure decreased after frozen storage for 120 days, pre-cooking treatment could significantly enhance the thermal stability of frozen noodles, and pre-cooking 5 min could reduce the damage of frozen storage to gluten network structure. Therefore, in the production process of frozen noodles, selecting the appropriate pre-cooking time could improve the frozen storage quality of noodles. The research would provide a theoretical basis for regulating the quality of frozen noodles and frozen storage quality.